Shock-absorber.



W. A. JOHNSON.

SHOCK ABSORBER. urmcuxox FILED mus, 1910.

Patented Nov. 8, 1910.

. 7 j 6 Im I mm X 2 8 hr j 5-? 9 [W 6 J 1 7 13w emfor' *6 of Illinois, have invented certain new and '30 .si es of the piston to equalize the pressure Fig. 2 is'a central verticalsection; and F g,- a valve and its H 5 preferably providinga stufling-box exten- WILLIAM A. JOHNSON, OF CHICAGO, ILLINOIS.

SHOCK-ABSORBER.

'ipplication filed June 8. 1910.

To all whom it may concern:

Be it known that I, "inunn A. Joiixson,

I a citizen of the United btates, residing at I Clues o, 111 the county of Cook and State useful Improvements in Slmck-Absorbers, of which the following i.-: a specification.

M invention relates to hnproven'ients in shoc absorbers, and has-for :ts general ob- 1.0 ject to provide an improvement in pneumatic shook absorbers for automobiles or other vehicles whereby the device is adapted-when in any position to otter an air-cushion res'istanee to sudden reltitive movement of the parts to which the opposing elements of the structure are connected, and whereby it is adapted to operate substantially without recoil.

In generahiny invention provides a cheap, eflicient, durable, device, by which a piston member (for; attachment to one relativel movable part of the car), working in a cy inder Sfor attachment to the other relatively inovab e part of the car) serves when moved in either direction in the cylinderto compress the air toward that end of the cgtliner until its movementis stopped an reversed, and then immediately to open a.passa e of communication between opposite and to prepare the'pision to oppose its movemerit-from the 'position' just attained.

\ In the drawings Figure lis'a side eleva tion of a structure embodyingmy invention j 3 IS an enlarged detail of,

surrounding parts.

Referring'fto the cylinder closed atone end by a: head, 6, pro- 40-videdI- w1th a. lug, 7, havin an aperture,

whereby it mayconvenient ybe attached to thespring of an automobile, or to one of any v two relatively moving parts. 9 indicates a head 'f0l the oppositeend of the cylinder sion, 10,?snitably packed, as at 1 1, for cooperat-ion with"- h ;.p ston rod, to be desctibed, and covered by thdc'ap, 1'2. v 14 indicates-a hollow piston rod working through the stufiing box strncture,;the ch'annel or duct, 15, throu h said-rod being closed at its outer end, as, or example, by a screwthreaded fitting 16, carryir-ig a ring, 18, whereb connection of the piston r0 ay Specification of Letters'latent.

rawings, 5 'i gi a y floosely into the open cha'nne be ma e tothe car body or other relatively movable element PutentedNov. 8, 1910. Serial No. 585,789.

Thus, it will be seenthat the construction thus far described provides the cylinder 5 as a completely closed structure, thejinterior of which has no communication with the extenor air.

At its inner extremity, thehollow piston rod, 14, is screw-threaded, as at 20, to receive a lock nut,' 21, and a piston 22, closely fitting the cvlinder. The piston, 22, extends 06 somewhat yond'the extremity of the valve rod rope'r, 14, and a short section, 14 of sim' ar tubular stock to the piston rod is screwed intd'the piston andvloeked' therein by a nnt-,23 Th*faces of the piston are 10' ""dished, soithat the nuts, 21 and 23, lie between the edgelenes of the'piston. Within the portion of t a hollow piston rod encompassed by the plston, I; provide a valve chamber 24,- for'nied by counterboring', the 76.

end ofthe piston-rod,- 14, so that a shoulder or'seatis" 'rovided suiironndingrthe central channeh jlig section, 14', of thevalve .rod is made sijifflifffonrthebalance thereof primarily to facilitate the construetionjo of thi"-en1a r'2ed valve chamber-within the piston-rod; Ports,'2 5, ifefiect communication etween the interior channel, 15,,off the tubular piston rod-14, and'the cylinderehamber on" that side-of the pistonthr'ou h'which 86 the rod 14- extendssothat'in' then sence of any restriction by the valve, a passag'e .fo'r. .communicatw' btween; the-cylinder chembers on opposite sides of the piston 15. Pro

' vi'ded it E15, -'valve 90 a b s- Wheres 2 arranged to make act w'it fiandiseat 95 upon c'orres ends of the -chamber 24. As bestshoi l 175 fi'g g5 j out its-entilj'ejl' (which would be "referably. considerab y. A

w giiiilmi .7mm y u te in the head Got-the cylinder an extending 15} of the tonrod to a distancef' sufli'eient' to maintain its'engagement with the-piston rod through not an normal movement of the-letter operatiomwheneverthepp ston is moved viith .respactto the cylm in either direction.

engagement of the-valve der, the frictional I 26 with its guide rod- 27 prevents saidvalye -from moving until the movement ofthe piev ton has seated itlagainstiand caused it to greater than its: I

'elose the opening, 15, at the rear end of the valve chamber with reference to the direction of piston movement. This seating of the \':|l\'l" closes the passage for C(MIIIHLUIICH- tion bet ween omiosite sides of the piston and confines, on the side of the piston in the direction of advunve tl'wi'utl, a body of air which acts as with constantly iimreasing force to check the advance of the piston. .W'hen' the piston atlviince ceases, the compressed air naturally tends toeuuse a. recoil of the piston to initial position, but the instant that -the' recoil or return mo'venrent of the piston con'unences to take 111300 the retardation of the valve 26, due to fric tional engagement with its guide rod, 27, permits the piston so to move relative to the valve. 26 that the valve-is uns'euted and the passagefor communication between the two sides of the piston is opened so that pressureinstz-lntlv equalizes Then,

I ifthe return movement of tinues due to Y the vehicle parts, the valve seat-s 1n the op:

ment of the pistonifrom the lastposi-tion which ithad attained.

that,-regarrlless.of'the position of'the piston -in the ,oyl-inder, the: (le'vi'cefis cox iditioned to' offer resistance torela-tive movement between the vehicle 'pa'rts {hit-,{Wllli movement has taken place, thein 'either direction, and

d evi eei resistsjretlirnj movement "between the .4 WhIleQI have-herein -described in some dE-' tail-aj- -"paliticulur embodiment of my invenit will u the mechanical ern 'odiment the spirit of "-the :inWa tion-Qand Ari-thin -the scope 'of'the' Lappende'd lainie. 3

, p o sage therethron'gh" from one side to other o fithe isms, v 1] ve eontro'll a resilient cushion tendingthe piston ooncontinuing lllfivelllel'ltbetween to check any 1nove-.-

Thus. it will he seen 'eylinder, a I tending through an end of piston and piston rod structure providing an form a valveeha'rnb position. thnsattaine'd, thereefl'eetively to'preven't detrimental recoil, arid so to safve lmduestra-ins upon the vehicle the openingfor .oonnnunioation beepparent that 'cha'nflj s. might position. of the rising at icylin' ied-with n pas f fllud communicationable in either direction with the portion of the passage which it controls, and also reltitherein providingflan axial munication between -eylin opposite sides of the piston, a'valve said passage bodily earriedlhy-the both directions of the-movement?!) the ter, and relatively movable in said passage I dose the passage when inje'itlierfexln 'eme ireetion and thereby to oc-' so 2. In a shoclra-bsorher, a cylinder,episton' said relative move ent, andfa gniderodiivith which said va'lve .makes, frictional engagement to oppose the movement of thevalve with the piston in either direc tion and thereby to 060351011 its relative passage-closing niovemepts the aerial line of.

located on the cylinder.

said guide rodjbein'g carried by the cylinder and saiil-fvalve and-rodbeing In a device of the character described, a

piston therein; a piston 'rotl e245 the cylinder, sai d axial channel, enlarged Within-the piston to .mgs foreornmunieation from Gait valve chamber to :the {cylinder chajmbersonboth valve within and fittingsides of the piston, a loosely said a' xi'al chamber, adnpted [to close side of the.

piston, and ania x' ial.

er; and'providin i-open- .xvitlr eithercarried by the" cylinder extending 'tlhroughflthe valve.

chamber and, valve 'I'nakingiriotional con nection' with the; valve an attending into piston: In" testimony" -iI n the prse'nceo l-"4 Linn-Amie MAaY Arman; 

